> Dishonest consumers are the problem here, though
  > this is a problem that Groupon could do more to curtail.

This is what I was talking about. Groupon is not billing their subscriber list as a group of cheap-o's that will only use the discount and never return to the business and try to use the discount multiple times -- which they obtained by registering for Groupon multiple times under different names/aliases -- while they are there for their single visit.

If Groupon were to describe their subscriber list as such, then I could see their business start to decline, no?

It would be interesting to see what the average conversion-rate from one-time to repeat customer is based on Groupon coupons.